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Stroke, CardiovascularCLEARNCT04096248

CT (Computerized Tomography) for Late EndovasculAr Reperfusion

An observational study of Stroke, Cardiovascular, run by Boston Medical Center at 19 sites in 10 countries.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

The objective of this multicenter, retrospective, cross-sectional, chart review study is to compare outcomes (disability, complications and mortality) of patients with large vessel occlusion stroke presenting at late time window selected by either Non-Contrast CT (NCCT) only, advanced imaging with CTP (Computed… Read more about this study

Who is it for?
Ages 18 years and older
Conditions the study is for
Stroke, Cardiovascular
How many people
2,790 participants
Where
19 sitesin 10 countries
Study dates
15 Feb 2020to 1 May 2022
Phase
Observational
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 years and older
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Study population: Retrospective chart abstraction will be done on consecutive patients treated with a large vessel occlusion stroke who meet the inclusion and none of the exclusion criteria between January 1, 2014 and May 1, 2022.

Who may be able to join

  • Patients presenting 6-24 hours from last known well with large vessel occlusion stroke
  • ASPECTS score 5 or greater from last known well
  • January 1, 2014 to May 1, 2022

Who cannot join

  • -Time last seen well to treatment <6 hours from last known well

Trial locations and contacts

19 sites in 10 countries.

19 sites in 10 countries

United States7 sites

  • Grady Health; Marcus Stroke & Neuroscience Center

    Atlanta, Georgia, 30303

  • Boston Medical Center

    Boston, Massachusetts, 02118

  • Cooper University Health Care

    Camden, New Jersey, 08103

  • Upstate University Hospital

    Syracuse, New York, 13202

  • University of Toledo

    Toledo, Ohio, 43606

  • Mercy Health Neuroscience Institute

    Toledo, Ohio, 43608

  • University of Massachusetts

    Worcester, Massachusetts, 01655

Other trials in United States

Germany2 sites

  • University Hospital Carl Gustav Carus

    Dresden

  • Heidelberg University

    Heidelberg

Other trials in Germany

Japan2 sites

  • National Cerebral and Cardiovascular Center

    Osaka

  • National Hospital Organization Osaka National Hospital

    Osaka

Other trials in Japan

Switzerland2 sites

  • Bern University Hospital

    Bern

  • Lausanne University Hospital

    Lausanne

Other trials in Switzerland

Belgium1 site

  • UZ Leuven

    Leuven

Other trials in Belgium

Canada1 site

  • Centre Hospitalier de l'Universite de Montreal

    Montreal, Quebec, H2X 0C1

Other trials in Canada

Finland1 site

  • Helsinki University Hospital

    Helsinki

Other trials in Finland

France1 site

  • Universite de Lille

    Lille

Other trials in France

Portugal1 site

  • Hospital de Egas Moniz

    Lisbon

Other trials in Portugal

Spain1 site

  • Val D'Hebron

    Barcelona

Other trials in Spain

About this study

Official title: Non-Contrast CT vs CTP or MRI Selection vs Medical Management in Late Presentation of Large Vessel Occlusion Stroke, 6-24 Hours. A Multicenter Retrospective Study

The objective of this multicenter, retrospective, cross-sectional, chart review study is to compare outcomes (disability, complications and mortality) of patients with large vessel occlusion stroke presenting at late time window selected by either Non-Contrast CT (NCCT) only, advanced imaging with CTP (Computed Tomography Perfusion), MRI (Magnetic Resonance Imaging), or medical management.

Boston Medical Center (BMC) will serve as the main data coordinating site. Fifteen additional sites will seek local IRB approval or ethics approval. The aggregated de-identified data will be analyzed comparing types of interventions and outcomes by type of imaging or medical management.

Read the detailed description

Additional subgroup analysis that are planned include:

  1. Futile Reperfusion in the Extended Window. We will evaluate clinical, imaging and time metric factors associated with successful reperfusion yet poor outcomes (modified Rankin 3-6) in the 6-24 hour window. An evaluation of factors associated with symptomatic intracranial hemorrhage and mortality will be conducted.
  2. Pre-Stroke disability.
  3. EVT patients treated in the extended window compared to Medical Management
  4. EVT patients treated in the extended window with pre-existing disability vs. those without pre-existing disability
  5. Intravenous Thrombolysis in the Extended Window We aim to compare the safety and outcomes of bridging IVT in patients with acute ischemic stroke due to large vessel occlusion (LVO) who underwent EVT 6 to 24 hours after time-last-known-well.
  6. Medical Management vs CT selected Patients We hypothesize that in patients with large vessel occlusion in the anterior circulation presenting in the 6 to 24 hour window, patients who are selected by non-contrast CT and treated with endovascular therapy have more favorable outcomes (ordinal mRS shift) as compared to patients who are medically managed.
  7. Sex differences in the Extended Window In this study we aim to asses whether there are sex differences in clinical outcomes and safety of EVT in patients presenting in the 6-24 hour time window.
  8. Transfer Analysis

It is not well established whether transfer patients presenting in the extended window should have repeat imaging upon receipt at the endovascular center after an interim time window.

We hypothesize that within a 0 to 2, or 2 to 4 hour delay between images of the primary stroke center to receiving endovascular center, transferred patients in the extended window, who undergo thrombectomy with successful reperfusion will have similar outcomes in patients with or without repeat imaging at the receiving center.

We aim to compare the safety and outcomes of late-window bridging IVT vs. direct EVT for LVO acute ischemic stroke in the 6-24 hour time window.

Keywords
Large vessel occlusion, CT [Computed Tomography], CTP [Computed Tomography (CT) Perfusion], Modified Rankin score, ASPECTS (Alberta Stroke Program Early CT Score)
Medical subject headings
Myocardial Infarction

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Change in patients' disability based on a Modified Rankin Scale

    The Modified Rankin Score (mRS) is a 6 point disability scale with possible scores ranging from 0 to 5. Lower scores correlate with less disability/dependence.

    Measured: baseline, 90 days

Secondary outcomes (2)

  1. Intracranial hemorrhage incidence

    Number of cases of intracranial hemorrhage divided by appropriate denominator.

    Measured: 90 days

  2. Mortality rate

    Number of deaths divided by appropriate denominator.

    Measured: 90 days

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted19 Sep 2019
  2. Study start15 Feb 2020
  3. Primary completion23 May 2021
  4. Study completion1 May 2022

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Observational
Observational model
Other
Time perspective
Retrospective
Enrolment
2,790 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT04096248
Sponsor's protocol ID
H-37843
Acronym
CLEAR
Status last verified
Jun 2024
First submitted
17 Sep 2019
Last updated
4 Jun 2024
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
Undecided

Publications

  • Nguyen TN, Abdalkader M, Nagel S, Qureshi MM, Ribo M, Caparros F, Haussen DC, Mohammaden MH, Sheth SA, Ortega-Gutierrez S, Siegler JE, Zaidi S, Olive-Gadea M, Henon H, Mohlenbruch MA, Castonguay AC, Nannoni S, Kaesmacher J, Puri AS, Seker F, Farooqui M, Salazar-Marioni S, Kuhn AL, Kaliaev A, Farzin B, Boisseau W, Masoud HE, Lopez CY, Rana A, Kareem SA, Sathya A, Klein P, Kassem MW, Ringleb PA, Cordonnier C, Gralla J, Fischer U, Michel P, Jovin TG, Raymond J, Zaidat OO, Nogueira RG. Noncontrast Computed Tomography vs Computed Tomography Perfusion or Magnetic Resonance Imaging Selection in Late Presentation of Stroke With Large-Vessel Occlusion. JAMA Neurol. 2022 Jan 1;79(1):22-31. doi: 10.1001/jamaneurol.2021.4082.

    PubMed 34747975

  • Seker F, Qureshi MM, Mohlenbruch MA, Nogueira RG, Abdalkader M, Ribo M, Caparros F, Haussen DC, Mohammaden MH, Sheth SA, Ortega-Gutierrez S, Siegler JE, Zaidi SF, Olive-Gadea M, Henon H, Castonguay AC, Nannoni S, Kaesmacher J, Puri AS, Farooqui M, Salazar-Marioni S, Kuhn AL, Kiley NL, Farzin B, Boisseau W, Masoud HE, Lopez CY, Rana A, Abdul Kareem S, Sathya A, Klein P, Kassem MW, Cordonnier C, Gralla J, Fischer U, Michel P, Strambo D, Jovin TG, Raymond J, Zaidat OO, Ringleb PA, Nguyen TN, Nagel S. Reperfusion Without Functional Independence in Late Presentation of Stroke With Large Vessel Occlusion. Stroke. 2022 Dec;53(12):3594-3604. doi: 10.1161/STROKEAHA.122.039476. Epub 2022 Oct 14.

    PubMed 36252092

  • Siegler JE, Qureshi MM, Nogueira RG, Tanaka K, Nagel S, Michel P, Vigilante N, Ribo M, Yamagami H, Yoshimura S, Abdalkader M, Haussen DC, Mohammaden MH, Nannoni S, Mohlenbruch MA, Henon H, Sheth SA, Ortega-Gutierrez S, Olive-Gadea M, Caparros F, Seker F, Zaidi S, Castonguay AC, Uchida K, Sakai N, Puri AS, Farooqui M, Toyoda K, Salazar-Marioni S, Takeuchi M, Farzin B, Masoud HE, Kuhn AL, Rana A, Morimoto M, Shibata M, Nonaka T, Klein P, Sathya A, Kiley NL, Cordonnier C, Strambo D, Demeestere J, Ringleb PA, Roy D, Zaidat OO, Jovin TG, Kaesmacher J, Fischer U, Raymond J, Nguyen TN. Endovascular vs Medical Management for Late Anterior Large Vessel Occlusion With Prestroke Disability: Analysis of CLEAR and RESCUE-Japan. Neurology. 2023 Feb 14;100(7):e751-e763. doi: 10.1212/WNL.0000000000201543. Epub 2022 Nov 4.

    PubMed 36332983

  • Demeestere J, Qureshi MM, Vandewalle L, Wouters A, Strbian D, Nogueira RG, Nagel S, Yamagami H, Puetz V, Abdalkader M, Haussen DC, Mohammaden MH, Mohlenbruch MA, Olive-Gadea M, Winzer S, Ribo M, Michel P, Marto JP, Tanaka K, Yoshimura S, Martinez-Majander N, Caparros F, Henon H, Tomppo L, Dusart A, Bellante F, Ramos JN, Jesser J, Sheth SA, Ortega-Gutierrez S, Siegler JE, Nannoni S, Kaesmacher J, Dobrocky T, Salazar-Marioni S, Farooqui M, Virtanen P, Ventura R, Zaidi SF, Castonguay AC, Uchida K, Puri AS, Sakai N, Toyoda K, Farzin B, Masoud HE, Klein P, Bui J, Rizzo F, Kaiser DPO, Desfontaines P, Strambo D, Cordonnier C, Lin E, Ringleb PA, Roy D, Zaidat OO, Fischer U, Raymond J, Lemmens R, Nguyen TN. Outcomes of Bridging Intravenous Thrombolysis Versus Endovascular Therapy Alone in Late-Window Acute Ischemic Stroke. Stroke. 2024 Jul;55(7):1767-1775. doi: 10.1161/STROKEAHA.124.046495. Epub 2024 May 15.

    PubMed 38748598

  • Mujanovic A, Strbian D, Demeestere J, Marto JP, Puetz V, Nogueira RG, Abdalkader M, Nagel S, Raymond J, Ribo M, Michel P, Yoshimura S, Zaidat OO, Winzer S, Ortega-Gutierrez S, Sheth SA, Siegler JE, Dusart A, Haussen DC, Henon H, Serrallach BL, Mohammaden MH, Mohlenbruch MA, Olive-Gadea M, Puri AS, Sakai N, Klein P, Tomppo L, Caparros F, Ramos JN, Jumaa M, Zaidi S, Dobrocky T, Martinez-Majander N, Nannoni S, Bellante F, Rodriguez-Calienes A, Salazar-Marioni S, Virtanen P, Kaiser DP, Ventura R, Jesser J, Castonguay AC, Qureshi MM, Masoud HE, Galecio-Castillo M, Requena M, Lauha R, Hu W, Lin E, Miao Z, Roy D, Yamagami H, Seiffge DJ, Strambo D, Ringleb PA, Lemmens R, Fischer U, Nguyen TN, Kaesmacher J. Safety and clinical outcomes of endovascular therapy versus medical management in late presentation of large ischemic stroke. Eur Stroke J. 2024 Dec;9(4):907-917. doi: 10.1177/23969873241249406. Epub 2024 May 17.

    PubMed 38757713

  • Nguyen TN, Nogueira RG, Qureshi MM, Nagel S, Raymond J, Abdalkader M, Demeestere J, Marto JP, Sheth SA, Puetz V, Dusart A, Michel P, Ribo M, Zaidat OO, Siegler JE, Haussen DC, Strbian D, Henon H, Mohammaden MH, Mohlenbruch MA, Olive-Gadea M, Puri AS, Winzer S, Kaesmacher J, Klein P, Tomppo L, Caparros F, Ramos JN, Jumaa MA, Zaidi SF, Martinez-Majander N, Nannoni S, Vandewalle L, Bellante F, Farooqui M, Salazar-Marioni S, Virtanen P, Kaiser DPO, Wouters A, Ventura R, Jesser J, Mujanovic A, Shu L, Castonguay AC, Mansoor Z, Qiu Z, Masoud HE, Requena M, Peltola E, Hu W, Lin E, Tanaka K, Cordonnier C, Roy D, Yaghi S, Strambo D, Yamagami H, Fischer U, Jovin TG, Lemmens R, Ringleb PA, Ortega-Gutierrez S. Noncontrast CT Selected Thrombectomy vs Medical Management for Late-Window Anterior Large Vessel Occlusion. Neurology. 2024 May 28;102(10):e209324. doi: 10.1212/WNL.0000000000209324. Epub 2024 May 6.

    PubMed 38709999

  • Abdalkader M, Ning S, Qureshi MM, Haussen DC, Strbian D, Nagel S, Demeestere J, Puetz V, Mohammaden MH, Olive Gadea M, Winzer S, Yamagami H, Tanaka K, Marto JP, Tomppo L, Henon H, Sheth SA, Ortega-Gutierrez S, Martinez-Majander N, Caparros F, Lemmens R, Dusart A, Bellante F, Zaidi SF, Siegler JE, Nannoni S, Kaesmacher J, Dobrocky T, Farooqui M, Salazar-Marioni S, Virtanen P, Vandewalle L, Wouters A, Jesser J, Ventura R, Castonguay AC, Uchida K, Puri AS, Masoud HE, Klein P, Mansoor Z, Bui J, Kang M, Mujanovic A, Rizzo F, Kokkonen T, Ramos JN, Strambo D, Michel P, Mohlenbruch MA, Lin E, Kaiser DPO, Yoshimura S, Sakai N, Cordonnier C, Ringleb PA, Roy D, Zaidat OO, Fischer U, Ribo M, Raymond J, Nogueira RG, Nguyen TN. Sex Differences in Outcomes of Late-Window Endovascular Stroke Therapy. Stroke. 2024 Feb;55(2):278-287. doi: 10.1161/STROKEAHA.123.045015. Epub 2024 Jan 22.

    PubMed 38252759

  • Tomppo L, Martinez-Majander N, Qureshi MM, Nguyen TN, Nogueira RG, Nagel S, Demeestere J, Puetz V, Henon H, Olive-Gadea M, Marto JP, Dusart A, Ringleb PA, Zaidat OO, Haussen DC, Mohammaden MH, Abdalkader M, Raymond J, Ortega-Gutierrez S, Sheth SA, Yamagami H, Ramos JN, Caparros F, Kaiser DPO, Ribo M, Salazar-Marioni S, Tanaka K, Virtanen P, Puri AS, Siegler JE, Zaidi SF, Jumaa M, Lin E, Mayol J, Ventura R, Winzer S, Klein P, Bellante F, Cespedes J, Wouters A, Masoud HE, Shu L, Castonguay AC, Herweh C, Cheng M, Hu W, Roy D, Yaghi S, Lemmens R, Cordonnier C, Mohlenbruch MA, Strbian D. Outcomes of Witnessed Versus Unwitnessed Patients With Stroke After Endovascular Therapy in the Extended Time Window. Stroke. 2026 Feb;57(2):362-370. doi: 10.1161/STROKEAHA.125.052355. Epub 2025 Nov 12.

    PubMed 41221581

  • Winzer S, Kaiser DPO, Qureshi MM, Castonguay AC, Strbian D, Nogueira RG, Nagel S, Raymond J, Abdalkader M, Demeestere J, Marto JP, Yamagami H, Tanaka K, Sheth SA, Dusart A, Michel P, Olive Gadea M, Ribo M, Zaidat OO, Haussen DC, Henon H, Mohammaden MH, Mohlenbruch MA, Siegler JE, Puri AS, Kaesmacher J, Klein P, Tomppo L, Caparros F, Ramos JN, Jumaa M, Zaidi S, Martinez-Majander N, Nannoni S, Vandewalle L, Bellante F, Galecio-Castillo M, Salazar-Marioni S, Virtanen P, Wouters A, Ventura R, Jesser J, Mujanovic A, Shu L, Qureshi A, Qiu Z, Masoud HE, Requena M, Sillanpaa M, Hu W, Lin E, Cordonnier C, Roy D, Yaghi S, Strambo D, Fischer U, Ortega-Gutierrez S, Lemmens R, Ringleb PA, Nguyen TN, Puetz V. Endovascular Therapy for Late-Window M2-Segment Middle Cerebral Artery Occlusion: Analysis of the CLEAR Study. Stroke. 2025 Jul;56(7):1671-1680. doi: 10.1161/STROKEAHA.124.048840. Epub 2025 May 22.

    PubMed 40405459

  • Marto JP, Qureshi M, Nagel S, Nogueira RG, Henon H, Tomppo L, Ringleb PA, Haussen DC, Abdalkader M, Puetz V, Zaidat OO, Demeestere J, Ramos JN, Ribo M, Olive-Gadea M, Mohammaden MH, Ortega-Gutierrez S, Sheth S, Yamagami H, Dusart A, Raymond J, Caparros F, Kaiser D, Tanaka K, Virtanen P, Puri AS, Siegler JE, Zaidi SF, Jumaa MA, Lin E, Requena M, Michel P, Winzer SM, Klein P, Nannoni S, Bellante F, Salazar-Marioni S, Galecio-Castillo M, Wouters A, Ventura R, Mujanovic A, Shu L, Castonguay AC, Jesser J, Masoud HE, Kaesmacher J, Hu W, Roy D, Yaghi S, Asdaghi N, Strambo D, Lemmens R, Strbian D, Cordonnier C, Mohlenbruch M, Nguyen TN. Endovascular Therapy for Patients With Low NIHSS Scores and Large Vessel Occlusion in the 6- to 24-Hour Window: Analysis of the CLEAR Study. Neurology. 2025 Apr;104(7):e213442. doi: 10.1212/WNL.0000000000213442. Epub 2025 Mar 20.

    PubMed 40112237

  • Siegler JE, Koneru M, Qureshi MM, Doheim M, Nogueira RG, Martinez-Majander N, Nagel S, Penckofer M, Demeestere J, Puetz V, Ribo M, Abdalkader M, Marto JP, Al-Bayati AR, Yamagami H, Haussen DC, Olive-Gadea M, Winzer S, Mohammaden MH, Lemmens R, Tanaka K, Virtanen P, Dusart A, Bellante F, Kaiser DPO, Caparros F, Henon H, Ramos JN, Ortega-Gutierrez S, Sheth SA, Nannoni S, Vandewalle L, Kaesmacher J, Salazar-Marioni S, Tomppo L, Ventura R, Zaidi SF, Jumaa M, Castonguay AC, Galecio-Castillo M, Puri AS, Mujanovic A, Klein P, Shu L, Farzin B, Moomey H, Masoud HE, Jesser J, Mohlenbruch MA, Ringleb PA, Strbian D, Zaidat OO, Yaghi S, Strambo D, Michel P, Roy D, Yoshimura S, Uchida K, Raymond J, Nguyen TN. CLEAR Thrombectomy Score: An Index to Estimate the Probability of Good Functional Outcome With or Without Endovascular Treatment in the Late Window for Anterior Circulation Occlusion. J Am Heart Assoc. 2024 Jul 16;13(14):e034948. doi: 10.1161/JAHA.124.034948. Epub 2024 Jul 9.

    PubMed 38979812

Questions about this trial

What is this clinical trial studying?

An observational study of Stroke, Cardiovascular, run by Boston Medical Center at 19 sites in 10 countries.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 3 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 4 Jun 2024. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 19 sites in United States, Germany, Japan, Switzerland, Belgium and 5 more countries. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Change in patients' disability based on a Modified Rankin Scale (time frame: baseline, 90 days). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT04096248, which also lists 11 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 4 Jun 2024.

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